Field of the Invention
The present invention relates to a thin film transistor substrate, and more particularly, to a thin film transistor substrate having two different types of semiconductor materials on the same substrate, and a display using the same.
Discussion of the Related Art
As the information society continues to develop, displays for depicting information are increasingly required in various ways to do more. Accordingly, various flat panel displays (or ‘FPDs’) are developed for overcoming many drawbacks of the cathode ray tube (or ‘CRT’), such as heavy weight and large volume. The flat panel displays include liquid crystal displays (or ‘LCDs’), plasma display panels (or ‘PDPs’), the organic light emitting displays (or ‘OLEDs’) and electrophoresis displays (or ‘EDs’).
The display panel of a flat panel display may include a thin film transistor substrate having a thin film transistor in each pixel region arranged in a matrix format. For example, a liquid crystal display (or ‘LCD’) displays video data by controlling the light transitivity of the liquid crystal layer using the electric fields applied across the liquid crystal layer. An organic light emitting diode display displays the video data by generating properly controlled light at each pixel disposed in a matrix manner as an organic light emitting diode is formed therein.
As a self-emitting display device, the organic light emitting diode display has the advantages of a fast response time, high brightness and a large viewing angle. An organic light emitting diode display (or OLED) using organic light emitting diodes of a high energy efficiency can be categorized as a passive matrix type organic light emitting diode display (or PMOLED) or an active matrix type organic light emitting diode display (or AMOLED).
As the development of personal electronic devices is becoming more active, display devices are being developed as highly portable and/or wearable devices. To incorporate a display device into a portable and/or wearable device, it is typically desirable for the display device to have low power consumption. However, with the conventional display technologies that have been developed to date, there are limitations on reducing power consumption.